Manual of conchology, structural and systematic; with illustrations of the species Volume 11

by George Washington Tryon

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1889 edition. ...The umbilical callous is reddish-brown. Alt. 9i, diam. 12 mill. Allied to T. crenulatus Mke., but differing in the coloration, deep sutures and umbilical callous. (Philippi.) Inside the reef at Tongatabv, off Nukalofa, 18fms. (Watson.) T. belcheri Phil., Zeitschr. f. Mal. 1849, p. 148; Conchyl. Cab., p. 302, t. 44, f. 3.--Watson, Challenger Rept,, p. 71. M. Rigata Philippi. PI. 41, figs. 32, 33. Shell conoidal, umbilicate, transversely closely sulcate, longitudinally closely striate; whitish; clouded with brown; whorls rather convex, the last rounded; base plano-convex, closely snIcate; umbilicus funnel-shaped, dilated, modified by two spiral callouses; columella arcuate, base truncate. (Phil.) The shell is somewhat flatly-conoidal, with 7 moderately convex whorls. The penult, has about 8 elevated lines, often in pairs; the last whorl has 12. They are decussated by dense oblique elevated growth-lines, as are also the slightly wider interstices. The base is level, and has about 8 narrow slightly elevated concentric line. The umbilicus is pretty narrow, but at the last whorl is widely funnel-shaped, showing two rounded spiral ribs, the lower terminating in the denticle at base of the columella. The aperture is rounded rhombic; the throat sulcate within; the columella produced outward with a somewhat reflexed margin. The color above is whitish or pale rust-yellow, with brown spots; beneath it is lighter with wavy interrupted brown lines, and darker umbilical border. Alt. 10, diam. 15 mill. This species stands midway between T. solandri and T. calliferus. It is separated from the first by the broader umbilicus, the slightly elevated spiral line, which on the base are narrow and crowded; from the last the much less developed umbilical callus...

188 pages, Paperback

First published January 1, 2008

About the author

1838-1888

American malacologist

Sometimes published as George Washinton Tryon Jr.